The dielectric relaxation of solid succinonitrile at microwave frequencies

The physical properties of succinonitril, NCCH₂CH₂CN, have made it suitable for inclusion in a program of research at microwave frequencies on solids possessing high dielectric constants because of the rotational freedom of their polar molecules. At radio frequencies, White and Morgan found no drop in the high dielectric constant when liquid, succinonitrile solidified at 54.2°C. Below the freezing point, the radio-frequency or static dielectric constant rose from a value above 50 to one above 80 at -42.6°, where it dropped abruptly in a 2.3° range to a low value typical of non-polar compounds, the optical dielectric constant.